Can’t comment on the building (I toured it once in search of a roommate, and it was fine, but I know nothing about the landlords, etc.), but the area’s great. I’m a single lady who has often walked home at 3am from 14th and Irving to just around this intersection, and I’ve never experienced any problems.
Potential red flags for your friend to consider:
–there’s a playground right next to this building, and it’s very loud during daylight hours. Depending on what floor the apartment is, I can see this being an issue for someone who teleworks often/enjoys sleeping in until 2p on Saturdays.
–14th Street itself is very loud. Ambulances, buses, people, etc. I’d try to get a window facing east for some semblance of peace
–Columbia Heights in general is a very diverse and busy place. This apartment has a lot of great things within comfortable walking distance, but with great things come many different kinds of people.
As for renting an apartment sight-unseen, I’ve…sort of done that. Our current apartment was being renovated from the earthquake and was, quite frankly, a disaster when I saw it. I just had to trust that the management would do a good job. They definitely did, and I love living in my current building and have no problems with the management company (Bernstein). Try researching the management via yelp, etc. and be on alert for red flags.